- 1 year ago
How to get the image from Chrome(Intermediate D3D Window),by use gdi and HWND?
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To capture the image from a Chrome window using GDI and the window's HWND (handle), you can follow these steps:
Obtain the HWND of the Chrome window you want to capture. You can use tools like Spy++ or the
FindWindow
function in code to get the HWND.Create a compatible device context (DC) using
CreateCompatibleDC
function.
cppHDC hdcScreen = GetDC(NULL);
HDC hdcCapture = CreateCompatibleDC(hdcScreen);
- Get the dimensions of the window using
GetClientRect
function.
cppRECT rect;
GetClientRect(hWndChrome, &rect);
int width = rect.right - rect.left;
int height = rect.bottom - rect.top;
- Create a compatible bitmap using
CreateCompatibleBitmap
function with the dimensions of the window.
cppHBITMAP hBitmap = CreateCompatibleBitmap(hdcScreen, width, height);
- Select the bitmap into the device context.
cppSelectObject(hdcCapture, hBitmap);
- Use the
PrintWindow
function to capture the contents of the window onto the bitmap.
cppPrintWindow(hWndChrome, hdcCapture, PW_CLIENTONLY);
- Save the bitmap to an image file using GDI functions such as
SaveHBITMAP
orSaveBitmapToFile
. Here's an example of saving it as a BMP file:
cppBITMAP bitmap;
GetObject(hBitmap, sizeof(BITMAP), &bitmap);
BITMAPFILEHEADER fileHeader;
BITMAPINFOHEADER infoHeader;
DWORD writeBytes;
memset(&fileHeader, 0, sizeof(BITMAPFILEHEADER));
memset(&infoHeader, 0, sizeof(BITMAPINFOHEADER));
fileHeader.bfType = 'MB';
fileHeader.bfSize = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) + bitmap.bmWidthBytes * bitmap.bmHeight;
fileHeader.bfOffBits = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER);
infoHeader.biSize = sizeof(BITMAPINFOHEADER);
infoHeader.biWidth = bitmap.bmWidth;
infoHeader.biHeight = -bitmap.bmHeight;
infoHeader.biPlanes = 1;
infoHeader.biBitCount = 32;
infoHeader.biCompression = BI_RGB;
HANDLE hFile = CreateFile(L"captured_image.bmp", GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
WriteFile(hFile, &fileHeader, sizeof(BITMAPFILEHEADER), &writeBytes, NULL);
WriteFile(hFile, &infoHeader, sizeof(BITMAPINFOHEADER), &writeBytes, NULL);
WriteFile(hFile, bitmap.bmBits, bitmap.bmWidthBytes * bitmap.bmHeight, &writeBytes, NULL);
CloseHandle(hFile);
- Clean up the resources by deleting the bitmap and releasing the device context.
cppDeleteObject(hBitmap);
DeleteDC(hdcCapture);
ReleaseDC(NULL, hdcScreen);
Make sure to include the necessary headers (windows.h
, wingdi.h
) and link against gdi32.lib
.
Remember that capturing the content of windows belonging to other applications, such as Chrome, may have legal and privacy implications. Ensure that you have the necessary permissions and adhere to applicable laws and regulations.